Integrated circuit modules often times called dual in-line packages or DIPs, contain a variety of miniaturized electrical circuitry and are widely used on printed wiring circuit boards manufactured by the Electronics and Communications Industry to form larger composite electrical circuits. A typical circuit module is a small modular package containing electrical circuitry that is coupled to metallic conducting leads extending outwardly from opposite longitudinal sides of the modular package. The conducting leads, hereinafter referred to as terminals, generally extend outwardly for a relatively short distance from the modular package and are formed downward at right angles to establish two aligned opposing rows of elongated terminals. Each circuit module terminal is relatively thin and flexible and may be easily damaged during the manufacturing process of assembling circuit modules on printed wiring circuit boards.
Circuit modules are sometimes assembled on printed wiring circuit boards, hereinafter referred to as circuit boards, by inserting the two aligned rows of circuit module terminals into holes formed on a circuit board and soldering the terminals to the board circuitry. The soldering of the terminals to the circuit board makes it difficult to remove and replace defective circuit modules.
Apparatus has been developed for use with circuit boards to facilitate the installation and removal of circuit modules. For example, the circuit module may be rigidly attached to a complementary cartridge in order that both the circuit module and cartridge may be inserted within a row of structured vertical spring terminals previously mounted on the circuit board. Several problems occur in that a cartridge is required to be attached to each circuit module and the fragile vertical spring terminals may be damaged before the circuit module and attached cartridge can be mounted on a circuit board.
Socket devices are often used to position and mount circuit modules on circuit boards. Many such socket devices generally employ an insulative body having a plurality of apertures formed therein each of which contains a spring contact receptacle. Each spring contact receptacle has a tail section that extends through the insulative body and which is soldered to the circuitry of a circuit board. The circuit module is mounted onto the circuit board by forcibly inserting the terminals into the socket apertures to expand or deflect the spring contacts to grasp the terminals and couple them to the circuit board. One of the problems with this type of socket is that a relatively high insertion force is required to plug the circuit module into the socket spring contact receptacles thereby often causing damage to the thin and flexible terminals of the circuit module.
Special sockets, sometimes referred to as zero insertion force sockets, have been developed for use in mounting circuit modules on circuit boards. Zero insertion force sockets are arranged so that the socket contacts by themselves exert little force on the circuit module terminals as the circuit module is inserted into the socket. Once the circuit module has been plugged into the socket, movable contact pressure inducing means are operated to exert a force to engage the circuit module terminals with the socket contacts.
In one type of zero insertion force socket a slide or cam must be operated from one end of the socket to cause the socket to force engagement of the circuit module terminals with the socket contacts. In another type of zero insertion force socket hinged side walls must be swung out from the socket to mount a circuit module on the socket. After mounting the circuit module the hinged socket side walls must be swung back and locked into position to engage the terminals with the socket contacts.
Manufacturing packaging techniques presently in common use require that circuit module sockets be mounted on a circuit board in high density arrays of sockets. A problem arises with the aforementioned zero insertion force sockets in that the density of circuit module sockets on a circuit board make it difficult to position slides, cams and hinged side walls of sockets so that circuit modules may be inserted in or removed from the sockets. In addition, the inconvenience of operating socket slides, cams and hinged side walls of sockets densely mounted on circuit boards makes it difficult to use mechanized means to insert circuit modules into circuit board sockets.
Accordingly, a need exists in the art for apparatus arranged to mount circuit modules in high density arrays on a circuit board. A need also exists for apparatus arranged to receive and mount a circuit module on a circuit board without damaging the circuit module terminals and without the necessity of operating the mounting apparatus to first open contacts to relieve the high insertion force and then close the contacts to engage the module terminals.